The conventional therapies using optical fibers, which insert optical fibers into tubular body structures including bronchial tubes, blood vessels or ureters, i.e., tubular organs, to induce change or treatment of lesion tissues, deliver light only in a straightforward or lateral direction. In the field of laser therapy, a technique for allowing light delivery in multiple directions is required.
Further, in order to treat tubular organs, lumens of tubular organs are to be expanded. To this end, catheters or stents are conventionally used. However, there is a disadvantage that the permanent treatment is impossible with such catheters or stents.
In addition, it is important to center optical fibers in the tubular organs in order to achieve a consistent therapeutic effect and a constant temperature distribution upon treatment of lesion tissues in tubular organs using optical fibers. Also, a mechanical device is further required to uniformly induce the expansion of tubular organs with a constant force.
Moreover, it is necessary to obtain information on a temperature distribution and an expansion range in tubular organs upon treatment of lesion tissues in the tubular organs. Conventional therapies using optical fibers, however, do not provide such function.